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1.
Indirect somatic embryogenesis was induced on leaf explants of greenhouse-grown Helianthus maximiliani plants. Leaves of the regenerated plants were used as starting explants for the induction of direct somatic embryogenesis.
Another cycle of somatic embryogenesis was induced on the leaves of regenerated plants. In both cases, leaf explants were
cultured on media containing different auxin/cytokinin ratios. The auxin/cytokinin ratio had an influence on the intensity
of embryo formation, germination and the capability to regenerate plants. Somatic embryogenesis was generally more intensive
on the medium with lower concentrations of 6-benzylamino-purine. Further, the percentage of regenerated plants was higher
when embryos were induced on high-cytokinin, low-auxin medium. Secondary somatic embryogenesis was induced on embryos by culture
in liquid hormone-free medium. Similar to direct embryogenesis the efficiency of secondary embryogenesis depended on the medium
used for the induction of the primary embryos. In contrast to the mostly low frequencies of conversion of secondary embryos
into plants that has been observed in other species, the percentage of regenerated plants from secondary embryos of H. maximiliani was quite high, although slightly lower than that obtained in primary embryos.
Received: 28 March 2000 / Revision received: 1 September 2000 / Accepted: 2 October 2000 相似文献
2.
This report describes a protocol for the regeneration of plants from protoplasts isolated from proembryogenic masses (PEMs)
in a suspension culture derived from the nucellar callus of mango (Mangifera indica L. cv 'Amrapali'). The maximum yield (24.6±1.1×106), with 81.04±4.1% viable protoplasts per gram PEMs, was obtained with an enzyme mixture containing 1.2% cellulase, 1.0% hemicellulase
and 0.6% pectinase. An optimum density of 5×104 cultured protoplasts per milliliter culture medium was required for the highest frequency (88.89±5.40%) of division. Dividing
protoplasts developed into microcalli that proliferated on medium supplemented with growth regulators (auxins or kinetin alone,
or auxins with kinetin) and produced somatic embryos after transfer to a growth regulator-free medium. The protocallus on
2,4-D-containing medium produced the maximum number (102.50±6.93) of somatic embryos. Maturation of somatic embryos depended
upon the presence, and the nature and combination of growth regulators in the medium during proliferation of the callus. The
mature somatic embryos germinated and developed into plants that were transferred to soil.
Received: 1 April 1999 / Revision received: 27 July 1999 / Accepted: 23 August 1999 相似文献
3.
Regeneration of Acacia mangium through somatic embryogenesis 总被引:2,自引:0,他引:2
Somatic embryogenesis and whole plant regeneration were achieved in callus cultures derived from immature zygotic embryos
of Acacia mangium. Embryogenic callus was induced on MS medium containing combinations of TDZ (1–2 mg/l), IAA (0.25–2 mg/l) and a mixture of
amino acids. Globular embryos developed on embryogenic callus cultured on the induction medium. Nearly 42% of embryogenic
cultures with globular embryos produced torpedo- and cotyledonary-stage embryos by a two-step maturation phase. The first
stage occurred on 1/2-strength MS basal medium containing 30 g/l sucrose and 5 mg/l GA3 followed by the second stage on 1/2-strength MS basal medium containing 50 g/l sucrose. Of the cotyledonary-stage somatic
embryos, 11% germinated into seedlings that could be successfully transferred to pots. Light- and scanning electron microscopy
showed that the somatic embryos originated from single cells of the embryogenic callus. Further, a single cell layer could
be detected beneath the developing somatic embryos that appeared to be a demarcation layer isolating the somatic proembryonic
structure from the rest of the maternal callus. A suspensor-like structure connected the globular embryos to the demarcation
layer. This is the first successful report of plant regeneration through somatic embryogenesis for this economically important
tropical forest species.
Received: 20 January 2000 / Revision received: 28 September 2000 / Accepted: 29 September 相似文献
4.
B. N. S. Murthy N. N. Vettakkorumakankav S. KrishnaRaj J. Odumeru P. K. Saxena 《Plant cell reports》1999,18(7-8):607-613
Several cultivars of hybrid seed geranium (Pelargonium×hortorum Bailey), previously shown to be recalcitrant in culture, produced somatic embryos at high frequency when explants were co-cultivated
with a morphogenesis promoting bacterium. This bacterium was isolated as an in vitro contaminant from cultures of geranium
seedling explants and identified as belonging to the genus Bacillus and species circulans. Co-cultivation of hypocotyl explants with the bacterium promoted somatic embryo formation and improved
both the frequency and quality of somatic embryos. In the cultivar Ringo Rose, the least responsive among the cultivars screened,
the embryogenic response was more than four times that of axenic cultures. Nearly 70% of these embryos converted into plantlets,
while the somatic embryos induced under axenic conditions developed poorly and plantlet formation was inconsistent. Among
the different treatments of bacterial culture tested (autoclaved culture, culture filtrate, sonicated bacterial culture, sonication
of bacterial culture followed by filtration, HPLC fractionation of crude bacterial lysate), only two HPLC fractions promoted
embryogenesis to a marginal degree. Co-cultivation of the explants with bacterium during the first week of induction was crucial
for obtaining high-frequency embryogenesis, indicating the role of bacterial stimuli during the induction process.
Received: 23 June 1998 / Revision received: 20 August 1998 / Accepted: 27 October 1998 相似文献
5.
Somatic embryogenesis induced by the simple application of abscisic acid to carrot (Daucus carota L.) seedlings in culture 总被引:3,自引:0,他引:3
Seedlings of carrot (Daucus carota L. cv. Red Cored Chantenay) formed somatic embryos when cultured on medium containing abscisic acid (ABA) as the sole source
of growth regulator. The number of embryos per number of seedlings changed depending on the concentration of ABA added to
the medium, with a maximum embryo number at 1 × 10−4 M ABA. Seedling age was critical for response to exogenous ABA; no seedling with a hypocotyl longer than 3.0 cm was able to
form an embryo. Removal of shoot apices from seedlings completely inhibited the embryogenesis induced by application of exogenous
ABA, suggesting that the action of ABA requires some substance(s) that is translocated basipetally from shoot apices through
hypocotyls. Histologically, somatic embryos shared common epidermal cells and differentiated not through the formation of
embryogenic cell clumps, but directly from epidermal cells. These morphological traits are distinct from those of embryogenesis
via formation of embryogenic cell clumps, which has been found in embryogenic carrot cultures established using 2,4-dichlorophenoxyacetic
acid or other auxins. These results suggest that ABA acts as a signal substance in stress-induced carrot seedling somatic
embryogenesis.
Received: 22 April 2000 / Accepted: 8 June 2000 相似文献
6.
B. A. Bergmann W. P. Hackett H. Pellett 《In vitro cellular & developmental biology. Plant》1996,32(3):161-164
Summary Somatic embryogenesis was observed with explants taken from four types ofAesculus tissue: (a) shoots of 4-wk-oldin vitro germinated excised embryos (seed fromA.×arnoldiana), (b) roots of 4-wk-oldin vitro germinated excised embryos (seed fromA.×arnoldiana), (c) shoots from newly forced 3-yr-old seedlings (A. glabra), and (d) newly forced shoots from a 30-yr-old tree (A.×arnoldiana “Autumn Splendor”). Shoots provided three types of explants, single node, shoot apex, and internodal section, and all exhibited
embryogenesis.
Proembryogenic masses developed in a few cases after 6 wk in culture but were more commonly seen after 3 mo. The yellow, friable
proembryogenic masses emerged from proximal cut ends of explants. Almost all cultures that formed embryos possessed leaves,
either from developing apical or axillary buds or from adventitious buds, prior to the emergence of proembryogenic masses.
Only tissues that had begun to senesce and had been exposed to cytokinin (benzyladenine at 5 or 25 μM) formed somatic embryos. Embryos with distinct cotyledonlike structures and root/shoot axes developed during the 10 to 16
wk following the inital emergence of proembryogenic masses. Enhanced frequency of embryogenesis was obtained by dark culture
of root and shoot explants from 4-wk-old germinated embryos (A.×arnoldiana) and by dark and cold (5°C) treatment of shoot tissue cultures derived from 3-yr-old seedlings (A. glabra). Embryogenic potential was greatest in the most juvenile tissue and least in the mature tissue. Five percent of shoot explants
taken from the 30-yr-old select treeA.×arnoldiana “Autumn Splendor” produced somatic embryos. 相似文献
7.
Hairy roots were obtained after inoculation with Agrobacterium rhizogenes strain NCPPB 1855 of the in-vitro-grown shoots of the cherry rootstocks Colt (Prunus avium×P. pseudocerasus) and Mazzard F12/1 (P. avium L.). Not all putatively transgenic roots were able to grow in hormone-free medium. Mazzard F12/1 roots, induced with A. rhizogenes, did not differentiate any shoot or embryo, while both somatic embryos and shoots differentiated from the transgenic roots
of Colt in medium containing 1 mg/l 6-benzylaminopurine and 1 mg/l 1-naphthaleneacetic acid. Somatic embryos were capable
of secondary embryogenesis, but few developed into whole plants. DNA hybridization showed both a different number of bands
and signal intensity in each of the five transgenic shoot clones and embryos examined. In a morphogenetic in vitro test, leaf
explants of the transgenic shoot clones showed an increased capacity to differentiate roots, although clones differed in their
sensitivity to the hormone ratio. Clones from the transgenic shoots had not only an increased rooting ability when grown in
vitro but also exhibited various hairy root phenotypes when cultured in vitro and when transferred into the greenhouse.
Received: 12 December 1996 / Revision received: 21 March 1997 / Accepted: 10 May 1997 相似文献
8.
Protoplasts were isolated from embryogenic suspension cultures derived from avocado (Persea americana Mill.) zygotic embryos and nucellus in an enzyme digestion solution consisting of 1% cellulase Onozuka RS, 1% Macerase R10,
0.2% Pectolyase Y-23, 0.7 M mannitol. 24.5 mM CaCl2, 0.92 mM NaH2PO4 and 6.25 2-[N-morpholino]ethanesulfonic acid (1.5 ml) mixed with 0.7 M MS–8P (2.5 ml). MS-8P medium consisted of Murashige and Skoog salts without NH4NO3, 1 mg l–1 thiamine HCl, 100 mg l–1 myo-inositol, 3.1 g l–1 glutamine and 8P organic addenda. Medium osmolarity was adjusted with 0.15 M sucrose and 0–0.55 M mannitol. Protoplast yields of 3.5×106 protoplasts g–1 were obtained. Growth and development of the protoplasts were significantly affected by osmolarity, nitrogen source, plating
density and culture medium dilution. Under optimum conditions, proembryos developed directly from embryogenic protoplasts
and subsequently into somatic embryos. Optimum conditions for somatic embryo development included the culture of protoplasts
at a density of 0.8–1.6×105 ml–1 in 0.4 M MS–8P for 2–3 weeks, followed by subculture in 0.15 M MS–8P at a diluted density of 20–40× for 1 month in darkness to obtain somatic embryos. Mature somatic embryos were recovered
on semisolid medium; however, a low frequency of plantlet recovery (≤1%) from protoplast-derived somatic embryos was observed.
Received: 9 February 1998 / Revision received: 4 May 1998 / Accepted: 15 May 1998 相似文献
9.
Rowena Y. Kelley Allan E. Zipf Darrell E. Wesenberg Govind C. Sharma 《In vitro cellular & developmental biology. Plant》2002,38(5):508-512
Summary Mature embryos from hulled, regenerable GP-1 (A. sativa L.), hull-less, recalcitrant Tibor (A. nuda L.) and reciprocal crosses were cultured in vitro on a putrescine- (Put) containing medium. Hormone-free Murashige and Skoog medium (MS-0) or shoot proliferation medium (SPM)
[2.0 mgl−1 (9.0 μM) 2,4-dichlorophenoxyacetic acid (2,4-D)], with and without 0.5 mM Put or 1 mM Put, were tested for effects on somatic embryogenesis and plant regeneration. Put/SPM (0.5mM) was the best medium for both somatic embryos (SEs) and plant numbers per gram of callus, regardless of genotype. This effect
was most evident in Tibor, which produced no somatic embryos or plants on SPM, a previously published regeneration medium,
and in Tibor ×GP-1, which produced reduced numbers of SE and plants on the remaining media. The number of SEs per gram of
callus for GP-1 and GP-1× Tibor showed little significant differences between the different media. Put treatments produced
plants from the four genotypes but the regeneration efficiency on Put-containing medium was similar or even better than on
SPM for explants containing maternal GP-1 germplasm. This suggests that Put-containing MS-0 medium can be used for testing
regeneration of other oat lines. In addition, SPM containing 0.5 mM Put can be used to induce significant regeneration of plants from normally recalcitrant genotypes. This improvement greatly
increases the number of potential germplasms for further transformation efforts. 相似文献
10.
Regeneration of diploid annual medics via direct somatic embryogenesis promoted by thidiazuron and benzylaminopurine 总被引:7,自引:0,他引:7
A. Iantcheva M. Vlahova E. Bakalova E. Kondorosi M. C. Elliott A. Atanassov 《Plant cell reports》1999,18(11):904-910
The development of a simple and rapid procedure for direct somatic embryogenesis from wild Medicago spp. (M. truncatula, M. littoralis, M. murex, M. polymorpha) has exploited various explants including meristematic zones. Phytogel-solidified medium supplemented with thidiazuron or
6-benzylaminopurine at different concentrations effectively promoted this process. The first somatic structures emerged within
20 days of culture initiation. Histological analyses confirmed the nature of the directly formed embryos. Secondary embryogenesis
was also observed. Cuttings of clusters of primary and secondary embryos were used for cyclic production of new embryo generations.
Regenerated plants with well-developed root systems on medium with reduced levels of macroelements and sucrose were easily
adapted to a greenhouse.
Received: 23 March 1998 / Revision received: 10 August 1998 / Accepted: 7 December 1998 相似文献
11.
The pitch-loblolly pine hybrid (Pinus rigida × P. taeda) has useful characteristics of the parents, but its exploitation is hindered by restrictions of conventional breeding and
propagation methods. This study was undertaken to establish an effective in vitro system for propagating pitch-loblolly hybrid
pine through somatic embryogenesis and to unravel the relationship between the efficiency of embryogenic tissue initiation
and zygotic embryo development. To initiate embryogenic tissue, megagametophytes of developing seeds were used as explants.
Seeds were collected weekly, examined, and tested during June and July 2004. The medium and seed collection date were the
most important factors for the successful somatic embryogenesis of P. rigida × P. taeda. Five embryogenic lines were obtained using a modified P. taeda basal medium, and the highest initiation rate was 0.55%, for seeds collected in 2 weeks, between July 3 and 16. Histological
observation revealed that zygotic embryos of those seeds were mostly at the proembryonic stage or in transition to precotyledonary
stages. For the successful maturation of somatic embryos, abscisic acid and gellan gum were needed in the medium. The results
show that, although further tests and development are required, somatic embryogenesis could provide a viable option for propagating
P. rigida × P. taeda hybrids. 相似文献
12.
Thiago E. R. Silva Luciana C. Cidade Fátima C. Alvim Júlio C. M. Cascardo Marcio G. C. Costa 《Plant Cell, Tissue and Organ Culture》2009,99(3):287-298
In order to develop a more efficient genetic transformation system for cacao somatic embryos, the effects of polyamines and
β-lactam antibiotics on somatic embryogenesis, hygromycin as selective agent, and different factors affecting uidA gene transfer have been evaluated. The polyamines putrescine, spermidine, and spermine significantly improved secondary somatic
embryogenesis in cacao. Spermine at 1,000 μM provided the best responses, increasing 6.7× the percentage of embryogenic callus
and 2.5× the average number of embryos per embryogenic callus. The β-lactam antibiotics timentin and meropenem, used for Agrobacterium tumefaciens counter-selection, had a non-detrimental effect on secondary somatic embryogenesis, depending on their concentration, whereas
the commonly used β-lactam cefotaxime inhibited it, irrespective of the tested concentration. Hygromycin showed a strong inhibitory
effect on secondary somatic embryogenesis of cacao, impairing completely the embryo production at 20 mg l−1. Following the criterion of GUS activity, the best conditions for T-DNA transfer into cotyledon explants from primary somatic
embryos of cacao were a sonication of the explants for 100 s, a 20-min incubation period in Agrobacterium solution, an Agrobacterium concentration of 1.0 (OD600), and cocultivation of the explants on tobacco feeder layers. These findings will have important implications for studies
on functional genomics of cacao. 相似文献
13.
The influence of environment in the culture vessel is a factor that has very little study in the process of somatic embryogenesis.
The present research was carried out with the objective to determine the effects of carbon dioxide on somatic embryogenesis
of Coffea arabica cv. Caturra rojo. Embryogenic cell suspensions were cultured under different carbon dioxide concentrations (2.5%, 5.0%, and
10.0%) in the gases mixture and two control treatments, one with passive exchange and the other with forced ventilation. The
results demonstrated that there were a larger number of somatic embryos formed with a concentration of 2.5% CO2. The differentiation of these somatic embryos of coffee in embryogenic cell suspensions (130 × 103 SE l−1) was also stimulated. The effects of CO2 on somatic embryogenesis were demonstrated when the control with passive exchange was compared with forced ventilation control,
because in the former, where there was an accumulation of CO2, the production of somatic embryos was greater. CO2 could stimulate the formation and differentiation of somatic embryos directly, which led to a modification of the pH patterns
of the culture medium or indirectly when producing changes in the pH that favored the somatic embryogenesis process. 相似文献
14.
A simple method to induce somatic embryogenesis from seeds of rapid-cycling Brassica napus is described. Seedlings cultured on Murashige and Skoog (MS) basal medium produced somatic embryos directly on hypocotyls
and cotyledons after 2 to 3 subcultures onto the same medium. A low pH of the medium (3.5–5) was more conducive to somatic
embryogenesis than a higher pH (6 and 7). Embryogenic potential of the seeds was inversely correlated to seed age: about 41–68%
of immature seeds between the ages of 14 and 28 days after pollination (DAP) formed somatic embryos compared to 0–11% of the
seeds obtained 29–37 DAP. About 54% of the somatic embryos produced secondary embryos after subculturing onto the same medium.
The embryogenic potential of the cultures has been maintained on MS basal medium for 2 years (12 generations) without diminution.
Up to 75% of the secondary embryos developed into plantlets on MS medium enriched with 10–6
M zeatin, and 40% of these produced flowers when transferred to an optimised flower-induction medium. Viable seeds were produced
in self-pollinated in vitro flowers.
Received: 15 February 2000 / Revision received: 18 July 2000 / Accepted: 19 July 2000 相似文献
15.
Compared responses of poplar cuttings and in vitro raised shoots to short-term chilling treatments 总被引:4,自引:0,他引:4
In woody plants, chilling stress occurs during the early spring growth and can have important economic consequences. The
aim of this study was to compare the reliability of two different experimental systems, 3-month-old softwood cuttings and
in vitro-grown shoots, to study chilling effects in a poplar clone (Populus tremula×P. tremuloides cv. Muhs1). Different parameters were recorded: lignin content, sucrose concentration and protein and fresh weight variation,
during a 2-week treatment at 10 °C. Two families of polypeptides of high molecular weight (110 and 116 kDa) were shown to
accumulate in response to chilling in both cuttings and microshoots. For some of the parameters studied, i.e. appearance of
some groups of polypeptides and reduction of fresh weight gain, both in vitro and ex vitro systems were suitable and produced similar results. In contrast, for some other observations, i.e. on sucrose concentration
and lignin content, the systems led to different conclusions. While sucrose and lignin contents were shown to increase in
cuttings submitted to chilling, no variation in lignin and only a small temporary peak of sucrose could be observed in microshoots
kept under chilling. These parameters seem not to be suitable for studying the response of poplar in the in vitro system in such a short-term study.
Received: 18 November 1999 / Revision received: 3 March 2000 / Accepted: 7 March 2000 相似文献
16.
Summary A procedure for regenerating Zizyphus jujuba Mill. (Chinese date) plants through repetitive somatic embryogenesis (RSE) was developed. Primary somatic embryos were produced
from cotyledon-derived cultures of germinated plants in vitro. The highest induction frequency of primary somatic embryogenesis (PSE) was obtained with a combination of 4.52 μM 2,4-dichlorophenoxyacetic acid (2,4-D), 0.49 μM indole-3-butyric acid (IBA), and 0.44 μM benzyladenine (BA) (17.4%). These primary somatic embryos were multiplied by RSE on media with different plant growth regulator
(PGR) combinations. The highest RSE frequency (51.3%), was obtained with 0.58 μM gibberellic acid (GA3). However, the highest number (4.4 per primary somatic embryo) of repetitive somatic embryos was obtained with 0.98 μM 6-r-r-dimethylallylaminopurine (2-iP). For germination of somatic embryos, different PGRs, cold and desiccation treatment were
tested. Desiccation of somatic embryos at 25±1°C for 2 wk was the best treatment for germination with epicotyl elongation
and root development. Of over 256 plants regenerated, 237 (92.6%) survived. 相似文献
17.
Cotyledon explants of immature ginseng zygotic embryos cultured on Murashige and Skoog medium lacking growth regulators formed
somatic embryos directly, most in a multiple state, fused together and to the parent cotyledon explants. When the cotyledon
explants of ginseng were pretreated with 1.0 m sucrose for 24–72 h, all the somatic embryos developed individually from all surfaces of the cotyledons and the number of
somatic embryos per explant was enhanced fourfold. Histological observation revealed that all the single somatic embryos from
preplasmolysed cotyledons originated from epidermal single cells, whereas all the multiple embryos from cotyledons without
pretreatment originated from epidermal and subepidermal cell masses. When the somatic embryos matured to the cotyledonary
stage, further growth ceased and they remained white, probably indicating dormancy. Gibberellic acid (GA3) (over 1.0 mg/l) or chilling treatment (–2°C for over 8 weeks) were prerequisites for the germination of somatic embryos.
Ultrastructural observation revealed that the cotyledon cells of somatic embryos without chilling or GA3 treatment contained numerous lipid reserves, dense cytoplasm, proplastids and non-activated mitochondria, whereas the cotyledon
cells of somatic embryos after chilling or GA3 treatment were highly vacuolated and contained well-developed chloroplasts and active-state mitochondria enclosing numerous
cristae, indicating that in-vitro-developed somatic embryos of P. ginseng may be dormant after maturing in a manner similar to zygotic embryos.
Received: 8 July 1998 / Revision received: 31 August 1998 / Accepted: 23 September 1998 相似文献
18.
D. P. M. Wilson J. A. Sullivan A. A. Marsolais M. J. Tsujita T. Senaratna 《Plant Cell, Tissue and Organ Culture》1997,47(1):27-32
A number of media constituents including sucrose, ammonium nitrate and plant growth regulators were evaluated in an attempt
to improve somatic embryo production in zonal geranium (Pelargonium ×hortorum) cv. Scarlet Orbit Improved. Somatic embryo production was characterized by the quantity and type of somatic embryo induced
by the treatments. Sucrose at 4% supported the highest number of total somatic embryos while improving the proportion of the
morphologically normal cotyledon-stage somatic embryos. Addition of ammonium nitrate also improved embryo production. With
1.89 mM ammonium nitrate, normal cotyledon-stage embryo development was increased by 53%; the proportion of normal cotyledon-stage
embryos decreased and abnormal embryos with leaves or serrated margins in cotyledons (fringed-shoot type) increased with higher
ammonium nitrate concentrations. The effect of plant growth regulators on somatic embryogenesis indicated that exogenous supply
of indole-3-acetic acid (IAA) at a range of 0.25 to 4 μM failed to promote somatic embryogenesis. In contrast, benzyladenine
(BA) up to 2.0 μM increased the total embryo number and the proportion of desirable cotyledon-stage embryos. There was no
interaction between IAA and BA. Our research has demonstrated that improvement in both quantity and quality of somatic embryos
can be achieved in zonal geranium. 相似文献
19.
The development of a rapid protocol for high-efficiency somatic embryogenesis and plant regeneration from seed-derived embryogenic
callus cultures of California poppy (Eschscholzia californica Cham.) is reported. The optimized procedure required less than 13 weeks from the initiation of seed cultures to the recovery
of plantlets and involved the sequential transfer of cultures onto solid Murashige and Skoog basal medium containing three
different combinations of growth regulators. All steps were performed at 25 °C. Friable primary callus was induced from seeds
of E. californica cultured on medium supplemented with 1.0 mg l−1 2,4-dichlorophenoxyacetic acid. The primary callus was transferred to medium containing 1.0 mg l−1 1-naphthaleneacetic acid and 0.5 mg l−1 6-benzylaminopurine to establish embryogenic callus and promote somatic embryogenesis. Regenerated plantlets were recovered
after the conversion of somatic embryos on medium containing 0.05 mg l−1 6-benzylaminopurine and showed normal development. Embryogenic callus was induced at a frequency of 85%, an average of 45
somatic embryos were produced per callus, 90% of the somatic embryos converted, and about 70% of the plantlets were recovered
in soil. The growth rate of somatic embryo-derived shoots could be increased by gibberellic acid treatment, but the resulting
plantlets were hyperhydritic.
Received: 14 February 1999 / Revision received: 27 April 1999 / Accepted: 14 May 1999 相似文献
20.
Somatic embryo formation and germination from immature embryo-derived suspension-cultured cells of Angelica sinensis (Oliv.) Diels 总被引:3,自引:0,他引:3
Embryogenic callus was induced from immature embryos of Angelica sinensis cultured on Murashige and Skoog (MS) basal medium. Embryogenic callus growth was more rapid on MS basal medium than on B5
or White medium. Embryogenic callus was used to establish a suspension culture and somatic embryos and germinating embryos
developed during the culture. A shaking speed of 80 rpm was found to be optimal for establishing suspension cultures, while
100 rpm produced more somatic embryos and germinating embryos with an initiation cell density of 0.2 ml packed cell volume/25
ml medium. Adding 0.3% agar to the liquid medium also stimulated the formation of somatic and germinating embryos. While no
plant growth regulators were needed for culture initiation and plant regeneration, the addition of 0.5–1 mg/l 2,4-dichlorophenoxyacetic
acid was needed to maintain the embryogenic suspension culture by preventing embryo germination. Forty percent of the germinating
embryos survived after culturing on filter paper moistened with liquid half-strength MS medium containing 3% sucrose. The
plants were successfully transferred into soil.
Received: 19 March 1997 / Revision received: 21 November 1997 / Accepted: 19 January 1998 相似文献